Tire Pressure Monitoring System (TPMS) Technical Service Bulletin for FedEx Release Date: March 25, 2011 I. SENSOR MOUNTING STYLES There are two different methods for securing TPMS sensors to wheels banded style.and valve stem mounted. Valve stem mounted sensors come in two different types. 1. VALVE STEM MOUNT Tire pressure sensor is secured to the wheel. Installs from inside the wheel through valve stem hole. Two different valve stem mount types: A. Sensor is secured to wheel with aluminum hex nut Sensor is single piece design with aluminum valve stem. The valve cannot be removed from the body of the sensor. Sensors on Sprinter vans typically use this type of mounting style.
Whenever this type of valve mount sensor is serviced several disposable components must be replaced: Aluminum hex nut Nickel plated valve core Valve cap Grommet B. Snap-in Style Two-piece design. Valve stem snaps into the wheel opening for the valve aluminum hex nut is not used. Replaceable valve stem is made of brass clad in rubber. Uses long plastic valve cap. K-Tool International TPMS Support (800) 762-6002, x3 2
Has exposed brass shoulder just below the valve cap threads. Valve stem is secured to the body of the sensor using a T-10 torx screw tightened to 12 in/lbs. (1.3Nm). T-10 torque limiting tool pre-set to 12 in/lbs is needed to properly tighten the torx screw to correct torque. Torque limiting tool can also be used to remove the torx screw. T-10 Torque Screwdriver K-Tool International TPMS Support (800) 762-6002, x3 3
T-10 Tips: i) Do not overtorque the T-10 torx screw. ii) iii) iv) Old torx screws and rubber valve stems should never be re-used. Rubber stem replacement kits include a valve stem and torx screw. Only the valve stem should be gripped while tightening the torx screw. The head of the torx screw MUST be in contact with the metal tag in the sensor body. This two piece snap-in style is manufactured by Schrader Electronics and was introduced by GM in 2007 on some models. It has since been specified into additional models. The rubber stem should be replaced whenever the tire is serviced. Ford introduced the same two piece snap-in style sensor in 2009 on their F- Series trucks. The Ford versions use the same triggering signal that their banded style sensor use. This is a different triggering signal than used by GM. 2. BAND MOUNT Sensor is strapped to wheel using an aluminum or plastic band; tightened similar to a hose clamp Only passenger vehicles manufactured by Ford uses banded style sensors. Designed to be mounted 180 away from the valve stem. Bands may slip. Beginning in the 2009 model year Ford began using a rubber stemmed, twopiece stem mounted sensor design in some models. K-Tool International TPMS Support (800) 762-6002, x3 4
Econolines manufactured in the 2009 model year and earlier use the band mounted style. Econolines manufactured in the 2010 model may use either the band mount or the stem mount. K-Tool International TPMS Support (800) 762-6002, x3 5
II. TRIGGERING SENSORS Tire pressure sensors are triggered several ways. 1. VEHICLE MOTION When the vehicle is in motion over a threshold speed (usually around 15 mpg) the sensors become active and transmit about once a minute. 2. AIR PRESSURE All TPMS sensors, by design, will respond to changes in air pressure in the tire. When the vehicle is stationary you can manually trigger sensors by Increasing or decreasing air pressure in the tire by 8 to 10 psi. This is the only way that some sensors can be triggered when the vehicle is stationary, although this type sensor will not be found on any GM, Ford or Sprinter models. 3. MAGNETIC FIELD This type of sensor has largely been phased out of production. They will not be found on any GM, Ford or Sprinter from the 2007 model year forward. 4. RADIO FREQUENCY (RF) SIGNAL When the vehicle has been at rest for a pre-determined period of time the sensor enters a state of sleep in order to preserve its battery life. This time period varies for each sensor but is usually ten to twenty minutes. Most sensors can be awakened using a 125 Khz radio signal. This frequency is consider low frequency and is often referred to as an LF signal. These low frequency RF triggering signals are uniquely encoded depending on the sensor type. Stated another way, different sensor types require different types of RF signals or codes to awaken them. The signal that awakens a Ford sensor will not awaken a GM sensor, even if the sensors look identical. The vehicle does not have to be in a learn mode in order to trigger the sensor. K-Tool International TPMS Support (800) 762-6002, x3 6
Technicians can perform two functions using the RF triggering capability of the PST tool. A. Sensor Diagnosis (i.e., is the sensor transmitting properly?) B. Perform a relearn procedure on vehicles that require a manual relearn. This will be primarily Ford and GM models. Most Chrysler branded products including the Sprinter and Sefl- Learning. No tool is required for the relearn. The vehicle will relearn itself simply by driving for about 15 minutes. Operating Tip: The PST tool is used in the exact same manner whether one is performing a relearn procedure or diagnosing sensors. K-Tool International TPMS Support (800) 762-6002, x3 7
III. PST TOOL OPERATION 1. SENSOR ACTIVATION TECHNIQUES USING THE PST The PST tool can be used to trigger sensors using either the Hunt Mode or Manual Selection Mode. A. Hunt Mode Hunt Mode is engaged by simply pressing and releasing the Activation button. The green power LED will illuminate and the tool will display a left to right scrolling effect on the four yellow LEDs. Hunt Mode may take anywhere from five seconds to two minutes to trigger the first sensor on a vehicle. Subsequent sensor activations on the same vehicle should yield results in ten to fifteen seconds. Activation Button B. Manual Selection Mode The PST tool can also be used in Manual Selection Mode to trigger the tire pressure sensors. Manual Selection Mode is recommended because you will get tool feedback much faster, usually within 15 seconds. Engage the Manual Selection Mode by pressing and releasing the Selection button until the desired LED pattern is displayed and then immediately pressing and releasing the Activation button. The Activation button must be pressed within 3 seconds of making an LED selection or the tool will shut off in which case simply reselect and activate. Different selection patterns are required for different types of sensors. To trigger Ford branded vehicles users should select the 1 st and 3 rd LEDs then press Activation. This pattern is used for both the Ford banded and the stem mounted style sensors. K-Tool International TPMS Support (800) 762-6002, x3 8
To trigger GM branded vehicles users should select all four LEDs then press Activation. To trigger the Sprinter users should select only the 2 nd LED then press Activation. Operating Note: The scrolling LED effect displayed after the Activation button is pressed is simply a visual indicator that the tool is in operation. It does not necessarily indicate Hunt Mode. 2. TRIGGERING TECHIQUES FOR SENSOR WITH DIFFERENT MOUNTING STYLES A. Triggering Stem Mounted Sensors PST tool should be positioned on the sidewall next to the stem, not on the rim. K-Tool International TPMS Support (800) 762-6002, x3 9
B. Triggering Band Mounted Sensors The most effective tool position is 180 away from the valve stem on the flat, tread side of the tire pointed in towards the rim. Position the PST tool HERE (recommended) or HERE i) If the user is unsuccessful on the first attempt in triggering a sensor, then reposition the tool slightly (i.e., change the angle at which the tool is positioned on the tire) and then attempt to trigger again. This is particularly true when working with band mounted sensors. ii) On band mounted sensors the sensor position may creep around the tire due to slippage of the band. If unable to get a sensor response from the 180 position after two triggering attempts then try again while roaming with the PST tool 8 to 12 inches in both directions away from the 180 position.. DISCLAIMER EVERY EFFORT HAS BEEN MADE TO ENSURE THE ACCURACY OF THE INFORMATION PRESENTED. HOWEVER, NEITHER K-TOOL INTERNATIONAL (KTI) OR SPX ASSUME ANY RESPONSIBILITY FOR THE ACCURACY OF THE INFORMATION. THIS INFORMATION IS SUBJECT TO CHANGE WITHOUT NOTICE. ALL INFORMATION PROVIDED IN THIS DOCUMENT IS PROVIDED"AS IS" WITHOUT WARRANTY OF ANY KIND, EITHER EXPRESSED OR IMPLIED, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE, OR NON-INFRINGEMENT OF INTELLECTUAL PROPERTY. NEITHER KTI OR SPX SHALL NOT UNDER ANY CIRCUMSTANCES BE LIABLE FOR ANY SPECIAL, INCIDENTAL, INDIRECT OR CONSEQUENTIAL DAMAGES, INCLUDING, WITHOUT LIMITATION, DAMAGES RESULTING FROM USE OF OR RELIANCE ON THE INFORMATION PRESENTED, LOSS OF PROFITS OR REVENUES OR COSTS OF REPLACEMENT GOODS. K-Tool International TPMS Support (800) 762-6002, x3 10